@Adero Hey man, I'll try to help, but please understand this is my experience only, and you should treat an item of this price nicely imo 
If you read 2 or 3 posts above, I asked if this could be shrunk because I did sized it too big, and the answer was that it would be difficult.
So I did try to wash at 30C and 40C with low spin (400) and the damn thing would effectively not move 
I could only shrink it by putting it in the dryer at medium heat for 25 minutes (kids don"t do this at home !)
Long story short I think you're very safe at 30C or 40C !
Sorry @Giles , I forgot to report the data 
For those interested, with the dryer, The item went from a size 35 to 34 only in waist and knee, and it lost 2 cm in the inseam.
All other measurements did not move at all.
Again be very careful ! Medium heat is not nothing and I did pull the item out of the dryer every 5 minutes from the 10th minute to measure it
Since I was in a public place (I don't own a dryer) I let you imagine how I did look...